At JFK, at least, DL does not prioritize voluntary bumps by status or even order of volunteering. Once a list has been assembled of volunteers, agents choose from it randomly. Factors include number of pax in party, final destination, and alternate transportation options. One agent told me, though, that even if all factors are even they will choose people from the top, bottom, and middle of list rather than starting at the top and working down. He cited security concerns, which I thought was a bit of a stretch.

Twice over the past year, I found that by being friendly with the agent, staying in close contact (without becoming annoying!), and *knowing* your options, you stand a pretty good chance to be chosen. On both occasions I presented the agent with an alternate itinerary; he was happy to save the time researching it and I got the flights I wanted - along with a $700 voucher each time.